1. Field of the Invention
The invention relates to a device for assisting with driving an automotive vehicle. The invention also relates to a method for assisting with driving an automotive vehicle.
The present invention relates to methods and devices that are intended to provide assistance with driving automotive vehicles, particularly when exterior luminosity is low and requires lights to be turned on.
2. Description of the Related Art
The light beams emitted by the illuminating devices with which vehicles are equipped are regulated by international regulations that set maximum and minimum allowable intensities, for example on a screen placed away from and on the axis of the illuminating device. These regulations have the aim of simultaneously:                providing the driver of the vehicle equipped with the illuminating device with a satisfactory illumination of the road scene toward which he is driving, so that he is able to apprehend his environment under the best possible conditions, and        ensuring that drivers of other vehicles are not dazzled, whether they are driving in the opposite direction (approaching vehicles) or in the same direction (vehicles in front).        
With the aim of meeting these regulatory aims and with a view to improving the comfort and safety of the driver, a plurality of solutions have been proposed. One thereof consists in using a device for assisting with driving composed of a pulsed illumination source synchronized with a variable transmission screen, in such a way that the illumination reaches its maximum value when the transmission coefficient of the screen reaches its maximum value, i.e. a maximum transparency, and in such a way that the illumination reaches its minimum value when the transmission coefficient of the variable transmission screen reaches its minimum value, i.e. a minimum transparency.
Thus, by virtue of this synchronization, the driver benefits completely from his lights, while decreasing the risk of being dazzled by exterior light sources, because the vision of the driver is greatly restricted when the transparency of the variable transmission screen is at its minimum.
Furthermore, the pulsed illumination does not dazzle the drivers of other vehicles since they perceive only an average illumination that is set to meet the aforementioned regulations.
Particular problems arise when the vehicle equipped with the device described above meets an approaching vehicle equipped with a device of the same type. In particular:                When the two vehicles are in antiphase, i.e. when the transmission coefficient of the variable transmission screen of the vehicle is at its minimum while the lights of the other vehicle are emitting light, the driver is unable to see (or is able to see but not as well) the lights of the other vehicle.        When the two vehicles are in phase, i.e. when their lights emit light at the same time and the transmission coefficients of their variable transmission screens are at their maximum at the same time, the drivers may be discomforted by the lights of the other vehicle.        